1. Field of the Invention
This invention relates to an intravenous (IV) spike for attachment to a container of a parenteral fluid. More particularly the invention relates to an IV spike and drip chamber having an automatic shut off mechanism which stops infusion into the patient when the container is empty. More particularly the invention relates to an IV spike and drip chamber having a shut off mechanism and a vent mechanism in the spike for removing air from the drip chamber when the container is changed.
2. Related Information
It is a common practice in treating patients, particularly patients who must be cared for under emergency conditions, to administer medications into the patient intravenously. An intravenous solution, commonly referred to as parenteral fluid, is fed from a container, bottle or I.V. bag, through a tubing and a catheter which has been inserted into the patient's vein. The catheter is secured to the patient by a strip of adhesive tape. The IV fluid container is punctured by a spike which often includes a drip chamber for calculating the flow rate and visual inspection that fluid is flowing (dripping) from the container into the tubing. In the past the container was monitored and when empty had to be changed. An automatic shut off mechanism in the drip chamber is preferred.
Automatic shut off mechanisms in IV container drip chambers are known in the art. See for example U.S. Pat. No. 5,722,961 to Fan. A problem arises with the spike disclosed therein when the container is changed. The air in the drip chamber cannot be removed. Generally the sides of the drip chamber are pressed inwardly to remove the air. However, the IV tubing must be disconnected from the patient to prevent the air from entering the vein. The shut off mechanism disclosed therein is also large and cumbersome in relation to the drip chamber and might become stuck in the open position in the chamber.
A standard IV spike with a vent for venting air into the container (bag or bottle) is disclosed in U.S. Pat. No. 5,533,647 issued to Lung Hsiung. This vent does not solve the problem of the air in the drip chamber when the container is changed.